Papers by Author: Alifee Ayatillah

Abstract: The synthesis of alkylpolyglucosides involves condensation of decanol with dextrose in the presence of mesoporous silica sol-gel as a catalyst. In this study, mesoporous silica was produced using sol-gel technique by converting tetraethyl orthosilicate (TEOS) into silica. The mesoporous silica was characterized using BET surface area measurement and X-ray Photoelectron Spectroscopy surface analysis. The specific BET surface area was 794m²/g. From the XPS analysis, the Si2p binding energy is 103.7 eV while the O1s binding energy is 532.8eV indicating the formation of Si-O-Si bond which attributed to SiO₂. Mesoporous silica has been found efficient to be solid catalyst for synthesis alkylpolyglucosides and easy to be separated. The reaction was carried out 8 hours at 110°C-120°C under vacuum condition. The mass determination of alkylpoluglucosides has been achieved by ESI LC-MS/MS (ToF) positive-mode giving a mass peak at m/z = 343.21 corresponding to [M+⁺ of alkylmonoglucoside peak at retention time 11.0 min.

Abstract: Different catalysts, namely various loading of perchloric acid on various supports; HClO₄/silica (SiO₂), HClO₄/silica gel (SG) and HClO₄/alumina (Al₂O₃) were tested for the direct addition reaction of oleic acid (OA) to form estolide compounds. The reactions were carried out under vacuum (2 mBar) for 10 hours at 70 °C under solvent-less conditions. LC-MS ToF of reaction products results showed chromatographic peaks for the presence of two new estolide compounds, oleic-oleic monoestolide acid (m/z 563.51, as [M-H]^-), and oleic-oleic diestolide acid (m/z 845.77 [M-H]^-). The optimum loading of HClO₄ for every support are 15 wt.% HClO₄/SiO₂ (SiO₂15), 10 wt.% HClO₄/SG (SG10) and 35 wt.% HClO₄/Al₂O₃ (Al₂O₃35). The SG10 turned out to be the best catalyst, achieving a final conversion of 97.5 % with 79.8 % selectivity to oleic-oleic monoestolide acid and 17.7 % selectivity to oleic-oleic diestolide acid. The activity and selectivity of the SG10 have been investigated and compared with homogeneous HClO₄. The optimum catalysts for every support were characterized by XPS analysis, BET, TEM and TPD-NH₃.